dns problems

back from holidays I had a lot of problems with dns and postfix
it seems some user added a sub domain
www2.subdomein.com
postfix stopped because he did not know the protocol www2
dns also stopped but I was lucky to have a second dns server.
After a lot of struggle I solved issues above.

Now some remaining questions...

How can I remove warning below.
(from http://www.dnsstuff.com)
WARNING. The parent servers (I checked with amsterdam.ns.dns.be.) are not providing glue for all your nameservers. This means that they are supplying the NS records (host.example.com), but not supplying the A records (192.0.2.53), which can cause slightly slower connections, and may cause incompatibilities with some non-RFC-compliant programs. This is perfectly acceptable behavior per the RFCs. This will usually occur if your DNS servers are not in the same TLD as your domain (for example, a DNS server of "ns1.example.org" for the domain "example.com"). In this case, you can speed up the connections slightly by having NS records that are in the same TLD as your domain.

This is how my pri.rayit.nl looks like.
What should I add and how can it be done in ispconfig?

rayit.nl. A 80.100.12.206
www A 80.100.12.206
localhost A 127.0.0.1
mail A 80.100.12.206

--------------------------------

Will it be possible in the future to add a third dns server?
And how to add default entries (I now need to add to every .nl domain a
a record localhost 127.0.0.1 (strange sidn? and a MX backup mail server entry, SPF records.. etc..)

How can I remove warning below.
(from http://www.dnsstuff.com)
WARNING. The parent servers (I checked with amsterdam.ns.dns.be.) are not providing glue for all your nameservers. This means that they are supplying the NS records (host.example.com), but not supplying the A records (192.0.2.53), which can cause slightly slower connections, and may cause incompatibilities with some non-RFC-compliant programs. This is perfectly acceptable behavior per the RFCs. This will usually occur if your DNS servers are not in the same TLD as your domain (for example, a DNS server of "ns1.example.org" for the domain "example.com"). In this case, you can speed up the connections slightly by having NS records that are in the same TLD as your domain.